To bypass the stock fuel system, we rigged a gravity/siphon setup using a jerrycan, fuel line, and a marine-type squeeze bulb. This is the same emergency system four-wheelers often use when their fuel pumps fail in the field (assuming the jerrycan is secured a bit better). The squeeze bulb primes the carb to start, then siphon action and gravity usually keep a mill limping along. A proper marine fuel tank is preferable for fire safety. Either way, keep a fire extinguisher close by.